CAS No. 2809-21-4
Molecular FormulaC2H8O7P2Molecular weight: 206.02
Structural Formula
Properties:
HEDP is an organophosphoric acid corrosion inhibitor. It can
chelate with Fe, Cu, and Zn ions to form stable chelating
compounds.It can dissolve the oxidized materials on these metals’
surfaces.HEDP shows excellent scale and corrosion inhibition
effects under temperature 250℃.HEDP has good chemical stability
under high pH value, hard to be hydrolyzed, and hard to be
decomposed under ordinary light and heat conditions. Its
acid/alkali and chlorine oxidation tolerance are better than that
of other organophosphoric acids (salt). HEDP can react with metal
ions in water system to form hexa-element chelating complex, with
calcium ion in particular. Therefore,HEDP has good antiscale and
visible threshold effects. When built together with other water
treatment chemicals, it shows good synergistic effects.
The solid state ofHEDPis crystal powder, suitable for usage in
winter and freezingdistricts. Because of its high purity, it can be
used ascleaning agent in electronic fields and as additives indaily
chemicals.
Specification:
| items | index |
| Appearance | Clear, Colorless to pale yellow aqueous solution | White crystal powder |
| Active content (HEDP)% | 58.0-62.0 | 90.0min |
| Phosphorous acid(as PO33-)% | 1.0 max | 0.8 max |
| Phosphoric acid(asPO43-)% | 0.6 max | 0.5 max |
| Chloride (as Cl-)ppm | 100.0max | 100.0max |
| pH (1％ solution) | 2.0max | 2.0 max |
| Density (20℃)g/cm3 | 1.43-1.47 | - |
| Fe ionppm | 10.0 max | 5.0max |
| Colour APHA (Hazen) | 30.0max | - |
| Acetic acid % | 0.5 max | |
| Ca sequestration (mg CaCO3/g | 500.0 min | |
Usage:
HEDP is used as scale and corrosion inhibition in circulating cool
water system, oil field and low-pressure boilers in fields such as
electric power, chemical industry, metallurgy, fertilizer, etc.. In
light woven industry,HEDP is used as detergent for metal and
nonmetal. In dyeing industry,HEDP is used as peroxide stabilizer
and dye-fixing agent; In non-cyanide electroplating,HEDP is used as
chelating agent. The dosage of 1-10mg/L is preferred as scale
inhibitor, 10-50mg/L as corrosion inhibitor, and 1000-2000mg/L as
detergent. Usually,HEDP is used together with polycarboxylicacid.
Package and Storage:
HEDP liquid: Normally In 250kg net Plastic Drum, IBC drum can also
be used as required HEDP solid: 25kg inner liner polyethylene (PE)
bag, outer plastic woven bag, or confirmed by clients.
Storage for ten months in room shady and dry place.
Safety Protection:
Acidity, Avoid contact with eye and skin,once contacted, flush with
water.
Synonyms:
HEDP;HEDP(A);ETIDRONIC ACID;1-Hydroxy Ethylidene-1,1-Diphosphonic
Acid; Hydroxyethylidene-1,1-diphosphonicacid(HEDP);
1-HYDROXYETHYLIDENEDIPHOSPHONIC ACID;Hydroxyethylidene Diphosphonic
acid(HEDP);1-hydroxy-1,1-Ethanediyl ester
